Fastening device for screening apparatus



May 7, 1929. L. E. sbL AN 4 FASTENING DEVICE FOR SCREENING APPARATUS Fild'qul zs, 1927 2 Sheets-Sheet 1 \1 ki- \n: h Ill/$1M Q May 7, 1929. L.E. SOLDAN 1,711,

FASTENING DEVICE IIIOR SCREENING APPARATUS Fil ed July 29, 1927 2Shets-Sheet 2 i6 f 7/ A Patented May 7. 1929.

"UNITED, STATES P TENT. oF icE.

LEWIS E. SOLDAN, OF BUFFALO, NEW'YORK, ASSIGNOR TO PRO'BUCTIVEEQUIP'l/I'Filll'i CORPORATION, 'OF CHICAGO, ILLINOIS, A. CORPORATION OFILLINOIS.

FASTENING DEVICE FOR SCREENING APPARATUS.

Thisinvention relates to a screen mounting.

very rapidly owing to the abrasion of the gritty material whichisoperated upon and this necessitates frequent renewal ,of the screen.The means heretofore employed for replacing a worn screen with a new onewere expensive in construction, difficult tooperate and requiredconsiderable time :for ejecting 'the change in screens, which isobjectionable on account of loss in out-put when the machine is idlewhich added to the requirement of special forms of screens, made thecost of screening such materials unduly high.

It is, therefore the object of this invention to provide a screenmounting which permits of takingordinary stock screening and readilyshaping the same for use and providing fastening means whereby thescreen can be eX- peditiously replaced with ease and with no appreciableloss of time.

In the accompanying drawings Fig. 1 is a side elevation of a siftingmachine equipped with my improved screen mounting.

Fig. 2 is a cross section taken on line 2--2 Fig. 1.' p

Fig. 3 is a fragmentary top plan view of the sifting machine.

Figs. 1 and 5 are fragmentary vertical. longitudinal section taken onthe era-respondingly numbered lines of Fig. 2.

Fig. 6 is a fragmentary vertical cross section, on an enlarged scaletaken on line 66 of Fig. 1.

Fig. 7 is a horizontal section taken on line 77 of Fig. 6.

Fig. 8 is a fragmentary vertical transverse section on an enlargedscale, taken on line 88, Fig. 3. r

Fig. 9 is a fragmentary top plan View on an enlarged scale of thesifting machine showing one of the tightening devices.

Similar characters of reference indicate like parts in the severalfigures of the drawings.

The shaking body or shoe of the sifting machine may be of any suitableconstruction and in the present instance comprises two uprightlongitudinal side walls 10, and trans verse end walls 11 connecting theends of the side walls.

vThe shoe may be shaken reciprocated or oscillated by various means wellknown in the trade and no particular means have therefore been shown foraccomplishing this function.

it-11in the shoe are arranged the means for detachably inountingthescreen whereby the separating effect is produced. This screenis'constructed of a fiat sheet of foraminous material such as woven wireor perforated sheet metal which is of the desired dimensions tosubstantially conform to the space within the shoe, and this sheet isbent so as to form a flat body 12, and two longitudinal flanges 13projecting downwardly from the opposite edges of the sheet.

At suitable intervals cross pieces extend across the space within theshoe each of which cross pieces preferably consists of two parallelbars15 arranged with a narrow space be tween them and secured at theiropposite ends to the inner sides of the-sidewalls of the shoe. On top ofthese cross pieces and adjacent to the side walls of the shoe arearranged two longitudinal supporting bars 14: which are spaced fromthese walls. The screen is placed within the shoe with the longitudinaledge portions of its body resting on the supporting bars 14 and itsdepending flanges 13 engaging with the outer sides of these bars, asshown in Figs. 2 and 8.

Means are provided for fastening the 1011 gitudinal edge portions of thescreen to the supporting bars which means are preferably constructed asfollows Arranged lengthwise of the longitudinal edge portions of thescreen are two clamping bars each of which is provided with an upperhorizontal flange 16 engaging with the upper side of one of thelongitudinal edges of the screen body and a lower flange 17 projectingdownwardly from the outer edge of the upper flange and bearing againstthe outer side of the adjacent longitudinal flange of the screen.

Each of these clamping bars is pressed at intervals against the cornerformed at each end of the screens between its body and flanges so as togrip this part of the screenhe- I tween the clamping bar and therespective supporting bar. In its preferred form this clamping deviceconsists of a plurality of clamping screws 18 arranged at intervalsalong opposite sides of the shoe and each screw inclining inwardly andprojecting through an opening 19 in the adjacent wall of I the shoe andbearing at its lower inner end against the outer corner of therespective clamping bar and provided at its upper outer end with ahandle or wheel 20. The external screw thread of each clamping screwworks in the internally screw threaded opening of a nut 21 arranged atthe top of ahollow bracket 23 secured to the outer side of the shoe sidewall around the adjacent opening 19. After this clamping screw has beentightened, loosening of the same, due to vibration of the shoe isprevented by a detent consisting of a spring 24 secured to the side walland engaging with one of a series of notches 25 arranged in an annularrow on the periphery of the handle 20. To prevent the inner end of theclamping screws from slipping off the clamping bar, a retaining lip 26is secured to the vertical flange of the clamping bar in position toengage this outer side of the screen at the lower end thereof, as bestshown in Fig. 8.

To prevent the material which is being sifted from passing downwardlybetween the longitudinal edges of the screen and the side walls of theshoe a closure provided which preferably consists of an inclined guideplate 27 extending upwardly and outwardly from the inner edge of theupper flange of each clamping bar, and a flexible curtain 28 of rubberor other suitable materia secured at its lower edge to the upper innerside of the guide plate and bearing with its upper edge against theinner side of the adjacent shoe wall. This closure not only prevents thematerial from escaping between the screen and the shoe but also directsall the material to the upper side of the screen so that the same issubjected to separating action of the same, and pern'lits the use ofscreening material of varying thickness. Y

Upon releasing the pressure of the clamping screws against the clampingbars the latter are automatically raised by means consisting preferablyof springs 29 each of which has the form of a strip extending throughone of the openings 19 and is secured at its inner end to the guideplate of the respective clamping bar while its outer end is secured tothe adjacent bracket 23, as shown in Figs. 2, 8 and 9. When the clampingbars have'been thus released and ele ated from the longitudinal edgeportions of the screen, the latter can be easily withdrawn. lengthwisefroin the shoe and its supports for inspection and repairing and ifdesired another new screen or one of a different size mesh may besubstituted therefor and so: cured in place, which operation can beeffected very quickly and readily and thereby reduce interruption of theoperation to a minimum. After the screen has been clamped at itsopposite longitudinal edges to the shoe the same is deflected upwardlybetween its longitudinal edges for the purpose of making the screen tautand enabling the material to flow freely over the same. The improvedmeans for the purpose shown in the drawings are constructed as followsThe numeral 30 represents two tightening bars arranged lengthwisebetween the underside oft-he body of the screen and the upper side ofthe cross pieces and each provided on its upper side with a facing 31 ofrubber or similar elastic material forming a cushion whereby thistightening bar engages the screen. These tightening bars are raised andlowered for putting the body of the screen under tension preparatory tousing the same or slackening the same preparatory toremoval by meanswhich preferably comprise a plurality of elbow levers 32 each of whichis arranged between the two bars of one of the cross pieces and pivotedthereto by a pin 83 so as to swing vertically, a link 3% connecting theupper arm of each elbow lever with the adjacent part of one of thetightening bars, a shifting rod 35 extending from the lower arm of eachelbow lever outwardly, an adjusting head 36 having a screw connectionwith the outer end of the shifting rod and guided in the adjacent wallof the shaking shoe, and a cam 37 pivoted on the outer end of the headand engaging the outer side of the respective shoe wall. Upon turningeach of the cams so that the low part of its face is arranged next tothe shoe wall then the outward pull on the rod 35 is relaxed and thecorresponding tightening bars are released and permitted to drop bygravity and thus loosen the tension on screen which movement of thetightening bars is aided by lowering means consisting preferably of leafsprings 38 each secured at one end to the underside of the adjacenttightening bar while its opposite end is secured to the adjacent crosspiece shown in Figs. 2, 3, and 5. Upon turning each of the cams so thatthe salient part of its face engages the shoe wall then the pull on therod 35 causes the elbow levers to be turned in the direction forelevating the tightening bars and raising the body of the screen so thatthe same is taut and ready for use. The turning of each cam ispreferably effected by a handle or lever 39 projecting laterallytherefrom and adapted in its tightened position to engage the outer sideof the adjacent shoe wall. as shown in Figs. 1, 2, and 6. In order toprevent this cam from becoming loose while the screen is in operationmeans are provided for locking the same in its operative position, forexample, a turn button 40 pivoted on the shoe 'wall and adapted toproject through a slot 41. in the hand lever 39 and to engage with theouter side of the same.

By turning the head 36 on the shifting rod 35 these parts maybe'adjusted relative to each other tosecure the desired tension on thescreen.

I claim as my invention 1. A sifting apparatus comprising a shaking shoeprovided with supports, a screen havinga body engaging the top of saidsupports and flanges engaging with the sides thereof, and clamping meansfor holding said screen in engagement with said supports, includingclamping bars each having a horizontal and a vertical flange engagingwith the top of said body and the outer side of the flan e oi thescreen, clamping screws inclined relative to the screen body and mountedon said shoe and engaging with said clamping bars, and brackets mountedon said shoe and having nuts which receive said screws.

2. Asifting apparatus comprising a shakingshoe provided with supports, ascreen having a body engaging the upper sides of said supports andflanges engaging with the lateral sides thereof, and clamping means forholding said screen in engagement with said supports, including clampingbars each having a horizontal and a vertical flange engaging with thetop of said body and the outer side of the flange on the screen,clamping screws mounted on said shoe and engaging with said clampingbars, and retaining lips arranged on. said bars and engaging with saidscrews.

3. A sifting apparatus comprising a shaking shoe having side walls andsupports adj acent tothe inner sides otsaid walls, a screen having abody resting on top of said supports and longitudinal flanges projectingdownwardly from said body and engaging the outer sides of said supports,clamping means com iirising bars having horizontal and vertical flangesengaging the top of said body and the side of the flange on. said body,inclined guide plates projecting upwardly and outwardly from thehorizontal flanges of said clamping bars and flexible curtains extendingacross the space between said guide plates and said side walls.

4. A sifting apparatus comprising a shaking shoe having side walls andsupports adjacent to the inner sides of said walls, a screen having abody resting on top of said supports and longitudinal flanges projectingdownwardly from said body and engaging the outer sides of said supports,clamping means comprising bars having horizontal and vertical flangesengaging the top or" said body and the side of the flange on said body,inclined guide plates projecting upwardly and outwardly from thehorizontal flanges of said clamping bars, and flexible curtains securedto the upper ends of said guide plates and engaging theirv upper endswith the inner sides of the walls of said shoe.

5: A sifting apparatus comprising a shaking shoe having side walls andsupports adj acent to the inner sides of said walls, a screen having abody resting on top of said supports and. longitudinal flangesprojecting downwardly from said bodyand engaging the outer sides of saidsupports, clamping means comprising bars having horizontal and verticalflanges engaging the top of said body and the side of the flange on saidbody, and means tending to raise said bars when the and the side of theflange on said body, in

clined guide plates projecting upwardly and outwardly from thehorizontal flanges of said clamping bars, screws mounted on said shoeand engaging said bar for holding them, and springs tending to raisesaid bars and connected at one end with said guide plates and mounted atthe opposite ends on said shoe. y I 7. A sifting apparatus comprising ashaking shoe, a screen secured to said shoe at its edges, and means fordeflecting said screen between its edges for tightening the samecomprising tightening bars adapted to engage with the underside of saidscreen, elbow levers mounted on the shoe. and connectedwith thetightening bars, and means for shifting said elbow levers.

8. A sifting apparatus comprising a shaking shoe, a screen secured tosaid shoe at its edges, and means for deflecting said screen between itsedges for tightening the same comprising tightening bars adapted toengage with the underside of said screen, elbow levers mounted on theshoe and connected with the tightening bars, and means for shiftingsaid. elbow levers comprising a shifting rod connected with each elbowlever, and a cam pivotally connected with each rod and adapted to engagesaid shoe.

9. A sifting apparatus comprising a shaking shoe, a screen secured tosaid shoe at its edges, and means for deflecting said screen between itsedges for tightening the same comprising tightening bars adapted toengage with the underside of said screen elbow levers mounted on theshoe and connected with the tightening bars, means for shifting saidelbow levers, and springs for depressing said tightening bars.

10. A sifting apparatus comprising a shaking shoe, a screen secured tosaid shoe at its edges, and means for deflecting said screen between itsedges for tightening the same comprising tightening bars adapted toengage with the underside of said screen, elbow levers mounted on theshoe and connected with the tightening bars, and means for shifting saidelbow levers comprising a shifting rod connected Witheach elbow lever, acam pivotally connected with'each rod and adapt- 7 ed to engage saidshoe, and means for holding said cam against turning.

11. A sifting apparatus comprising a shaking shoe, a screen secured tosaid shoe at its edges, and means for deflecting said screen between itsedges for tightening the same comprising tightening bars adapted to engage with the underside of said screen, elbow ed to engage said shoe. ahandle connected with said cam and having a slot, and a turn buttonpivoted on the shoe and adapted to pass through said slot of the handleand bear against the outer side of thesanie.

:12. A sitting apparatus comprising a shaking shoe provided with asupport having a horizontal top and a vertical outer side; a

screen having a horizontal body engaging with the horizontal top of saidsupport and a depending vertical flange engaging with the vertical sideof said support; a-clamping her having a horizontal flange engaging withthe top of said screen body anda vertical flange engaging with saidscreen flange; and an inclined clamping screw, arranged at an angle tothe screen body and mounted on said shoe and engaging with said clampingbar,

In testimony whereof I aflix my signature.

LEWIS E. SOLD AN.

